闽江口互花米草入侵年限对沉积物的硝化-反硝化影响

Effects of Invasion Years of Spartina alterniflora on the Nitrification and Denitrification of Sediments in the Min River Estuary

为了探究互花米草入侵年限对湿地沉积物氮素硝化-反硝化的影响,采集闽江口4个入侵时间不同的沉积物,采用时空互换方法研究不同入侵年限的互花米草对河口湿地沉积物硝化-反硝化的影响.结果表明:(1)氮的硝化速率和反硝化速率总体上随着互花米草入侵年限的长短呈现先下降后上升的趋势;(2)硝化速率与C/N呈极显著正相关,与含水率和NH;-N呈显著正相关,与NO;-N呈显著负相关,与pH、电导率均无相关关系.反硝化速率与NO;-N呈显著负相关,与pH、电导率、含水率、C/N,NH;-N均无相关关系;(3)闽江口湿地沉积物硝化速率均比黄河口、珠江口沉积物的硝化速率强,低于辽河口湿地沉积物;闽江口湿地沉积物反硝化速率均低于崇明东滩、辽宁河口和珠江河口沉积物.

In order to explore the impact of Spartina alterniflora invasion years on the nitrogen nitrification and denitrification of wetland sediments, four sediments with different invasion times in the Min River Estuary were collected, and the time-space interchange method was used to study the impact of Spartina alterniflora on nitrification-denitrification with different invasion period in wetland sediments. The results show that:(1) the rate of nitrogen nitrification and denitrification generally decrease with the length of Spartina alterniflora invasion, and then increase;(2) the rate of nitrification and C/N shows a very significant positive correlation. Moisture content is significantly positively correlated with NH;-N, significantly negatively correlated with NO;-N, and has no correlation with pH or conductivity;denitrification rate is significantly negatively correlated with NO;-N, and is significantly negatively correlated with pH, conductivity, Moisture content, C/N, NH;-N;(3) the nitrification rate of the sediments in the Min River Estuary wetland is stronger than that of the Yellow River Estuary and the Pearl River Estuary, and lower than that of the Liaohe Estuary wetland sediments;the denitrification rate of the Min River Estuary wetland sediments is lower than that of Chongming Dongtan and Liaoning Sediments and the Pearl River estuary.